Bird Opening starts with 1. f4. This opening is less popular for white than the 1.e4, 1.d4 or even 1.c4. White’s idea is to control the dark squares in the center without committing to the advance of the central pawn right away. But as we will see, the move f4 weakens the e1-h4 diagonal, which black can exploit.
Black has several continuations. Major choices are 1…d5, 1…c5 and 1…Nf6.
Black plays 1…d5
After 1…d5 2.Nf3 Nf6 3.b3 g6 4.Bb2 Bg7 5.e3 0-0 6.Be2 c5 7.0-0 Nc6 8.Ne5 Qc7 we reach themain set-up of the bird opening
White has played for the control of e5 square and occupied it with the knight. In case black exchanges on e5, white takes with the f-pawn and opens up the f-file for the rook. Therefore, black doesn’t prefer to take on e5.
On the other hand, black has completed the development and has achieved an objectively equal position. Black can play Be6 or a6-b5-Bb7 and bring the rook into play with Rad8.
The stonewall set-up
After 1.f4 d5 2.Nf3 Nf6 3.e3 g6 4.f4 white plays the stonewall set-up. As we have seen in the Stonewall attack, white’s idea is to strengthen the e5 square and occupy it with the knight. But white leaves a hole on the e4 square and also a long term problem of the development of c1 bishop.
Black plays 1…Nf6
The set-up can go along the same lines where white plays the fianchetto on b2 vs. black’s bishop on g7. After 1…Nf6 2.Nf3 g6 3.b3 Bg7 4.Bb2 0-0 5.e3 d6 6.d3
By delaying 1…d5, black maintained an additional option of playing 5…d6. Note that 5…d5 would lead to the position similar to previous line.
By playing 5…d6, black controls the e5 square and prevents Ne5. But leaves the e4 square free for white to control. Therefore white’s plan includes 6.d3-e4 with a different kind of set-up.
Black plays 1…c5
After 1…c5, white can easily continue playing the standard Bird opening set-up with 2.Nf3-b3-Bb2. But he also has an option of playing 2.e4, transposing into Sicilian Grand Prix attack.
Black can continue either with 2…Nc6, 2…d5 or 2…e6.
The From gambit
1.f4 e5 is the From gambit. This is a very strong weapon against the Bird opening. By sacrificing the pawn, black aims to take advantage of the weak dark squares.
If white plays 2.e4, the game transforms into the king’s gambit. Instead of black, it is now white who is ready to give up the pawn!
But if white accepts the gambit, then the main line goes 2.fxe5 d6 3.exd6 Bxd6 and black has a very strong initiative for the pawn.
Black is already threatening a checkmate with 4…Qh4+ 5.g3 Qxg3+ 6.hxg3 Bxg3#. Therefore white has to play 4.Nf3.
And here, black plays 4…g5, threatening g4. It is not easy to play for white here. The main line goes 5.g3 g4 6.Nh4 Ne7 7.d4 Ng6 8.Nxg6 hxg6 and black is again threatening to take on g3.
The natural move 9.Bg2 doesn’t work here because of 9…Rxh2!! 10.Rxh2 Bxg3+ and black remains a pawn ahead.
White has to play the only move 9.Qd3 to defend the g3 pawn.
Although white keeps the pawn, he will have difficult time coordinating his pieces. Black has enough compensation for the pawn.
Conclusion
With the Bird opening, white doesn’t really create any major challenges for black. Natural development is possible for both sides with an equal game. But black has a very strong weapon of the form’s gambit which white has to be prepared for. On the other hand, after 1.f4 e5 2.e4, black has to be ready to play the king’s gambit.
It is recommended to learn and practice the set-ups rather than memorizing move orders. The only lines worth remembering are the sharp and tactical possibilities of the Form gambit.